Distressing video shows the moment a 12-year-old boy was mercilessly beaten around the head for standing up to bullies on the school bus.

Arizona Sunrise Middle School student Parker Brockman is seen to sit at the back of the bus while he is taunted by two brothers who surround the seventh grader at the end of the school day.

Lashing out to stop the onslaught, Brockman is then set upon by at least two boys who reign down punches onto the top of the cowering boys head as he tries to avoid their blows.

Refusing to say anything when he returned home, the 12-year-old’s mother first heard of the attack when she received text messages and calls from worried parents whose children had told them what had happened on the school bus.

‘He didn’t say anything when he came home,’ said mom Tiffany Hunter to ABC 15

Confronting him about the incident, she discovered the truth about his bullying from her son.

They were ‘basically on top of me trying to punch my face, but I had my arms up blocking,’ said Parker Brockman.

‘He was insulting me, cussing at me, saying ‘hit me,’ said Brockman.

‘He was literally telling me to punch him the whole time. After awhile I swung a few punches.’

Responding violently, the boys only stopped hitting Brockman when he gave up fighting back.

‘He tries to be a tough guy. He does get targeted to get picked on,’ said Hunter.

According to Marty Macurak, a spokesperson for the Paradise Valley Unified School District, the two boys accused of punching Brockman were suspended from school and from the bus.

‘The situation was handled appropriately and in a timely fashion by both the bus driver and the school administrator,’ she said.

Macurak said the bus driver pulled over the bus to stop the fight.

According to Hunter this is a growing problem in Arizona and one that she is happy to raise awareness of.

A 2011 Youth Risk Behavior Survey conducted by the state found 7 percent of high school students did not go to school at least once because they felt they would be unsafe at school or on their way to or from school.

Nearly 28 percent of high school students surveyed reported having been in a physical fight “one or more times during the past twelve months.”

‘I just don’t want to see this happening to somebody else,’ said Hunter.

‘I have been the big advocate — if you know your child is being bullied at all, let the school know immediately.

‘This never would’ve happened if they were aware of the fact that these boys have been picking on other people.’